In her new film An Invisible Sign, Jessica Alba plays a reclusive math prodigy. We know this because she wears pigtails, constantly shoves her bangs out of her face, and sees numbers when she compulsively raps on walls and trees. It’s also more than a little bit ludicrous.

Alba is one of a category of actresses who play a certain role, and that does not include a socially awkward genius. These women portray the frazzled, Type-A, emotionally wounded protagonists of romantic comedies; occasionally the take-no-prisoners action heroines; and (in more meta roles) the glamorous superstars we can only dream of becoming.

We can’t imagine these ladies as softspoken, genuinely insecure (different from neurotic, which we see often) types because it’s unlikely that they were ever that unfortunate in the social skills realm. And yet, they turn to these roles… why? To avoid being pigeonholed, to garner more respect from their fanbase, to impress Oscar and Golden Globe voters?

We can probably trace the trend back to Denise Richards as Christmas Jones (that’s actually her name) in The World Is Not Enough. Bond girls, while always babes, usually fall into two categories: Stern or brainy. Richards was miscast in the latter, as a nuclear physicist who can’t even pronounce “nuclear” properly. Her chosen outfit of a tank top and short-shorts didn’t help her case, either.

Similar to Alba’s role is Gwyneth Paltrow‘s turn in Proof, where she played an unstable mathematician struggling with her father’s death and her own tenuous grip on sanity when she believes that the proof she discovers in her father’s desk was actually written by her. Opinions are split on Paltrow, with some saying that this was a role to help her move past her ingenue status; others say she looks befuddled by her lines. We’ve got just one thing to say: GOOP.

Tara Reid playing archaeologist Aline Cedrac in the video game-inspired horror flick Alone in the Dark was just offensive, since she looked more like someone’s fantasy than an actual scientific expert. She should stick to party-girl roles — I say this not to be offensive, but because she’s at her best when she’s spoofing her own image. (And in the Big Lebowski mock-sequel.)

Scarlett Johansson in Iron Man 2 toes the line of acceptability, because her character Natasha Romanoff uses her looks to get the job that her brains qualify her for — assistant to Tony Stark (Robert Downey, Jr.). It’s only after Tony’s hired her and flirted/shown her Stark Enterprises’ secrets that we discover she’s actually the secret agent Black Widow. So, she gets grudging respect for playing a bombshell hiding her real weapon.

Our lesson for today: Unless it’s satirical, generally slapping glasses on a hot girl who more often plays glamorous roles is not enough to sell her as a genius.